KR20180000121U - Separator core and separator roll - Google Patents

Abstract

The edge of the end portion on the outer peripheral surface of the outer cylindrical member 101 is chamfered in a straight line for the purpose of realizing the separator winding which effectively removes the deformation at the end portion and secures the strength And a separator winding core in which a separator core for a non-aqueous electrolyte secondary battery is wound on the separator winding core is provided, and a method of manufacturing the separator winding body is provided.

Description

[0001] SEPARATOR CORE AND SEPARATOR ROLL [0002]

The present invention relates to a separator core used when a separator for a nonaqueous electrolyte secondary battery is wound and a separator winding wherein a separator for a nonaqueous electrolyte secondary battery is wound around a separator core.

Patent Document 1 discloses an example of a shape relating to a separator winding core (hereinafter also referred to as " core ") wound when a manufactured separator is supplied as a product in a continuously produced separator while being transported by a transportation system such as a roller .

The core disclosed in Patent Document 1 has an outer cylindrical member to which the separator is wound, an inner cylindrical member which functions as a bearing for holding the shaft, a support member (hereinafter also referred to as a " rib ") connected to the outer cylindrical member and the inner cylindrical member, And the produced separator is supplied as a wound body to the outer cylindrical member.

Japanese Laid-Open Patent Publication No. 2013-139340 (published on July 18, 2013)

Incidentally, the above-mentioned core is often produced by resin processing by injection molding, which injects a resin as a raw material into a mold. At the end of the mold corresponding to the edge of the core in injection molding, the flow of the injected resin is high and the molecular orientation of the resin is deformed, so that residual stress is generated in the produced core.

As described above, since the core in which residual stress is present has a reduced strength, deformation of the core becomes large when the separator is wound. If the deformed core continues to be wound with the separator for a long time, the separator will be deformed, leading to deterioration in quality.

The present invention has been made in view of the above problems, and an object of the present invention is to realize a separator winding core in which deformation at an end portion is eliminated and strength is secured.

In order to solve the above problems, a separator winding core according to the present invention is a separator winding in which a separator for a nonaqueous electrolyte secondary battery is wound. The separator winding core includes an outer cylindrical member, an inner cylindrical member formed on the inner side of the outer cylindrical member, And a plurality of support members extending in a radial direction between the inner cylindrical member and the outer cylindrical member and connected to both of the support members, wherein the edge of the outer peripheral surface of the outer cylindrical member is chamfered in a straight line.

According to the above configuration, it is possible to efficiently remove the deformation that has occurred at the end of the outer cylindrical member. Therefore, it is possible to provide the separator winding with a strong strength and little deformation, while sufficiently securing the surface on which the separator is wound.

Further, in the case of chamfering the end portion on the outer peripheral surface of the outer cylindrical member, considering the safety of the operator in the process of the separator winding member and the relieving of impact upon falling of the core, , And R chamfer). However, in order to sufficiently remove the end portion where the deformation remains by chamfering the end portion, it is necessary to take a larger dimension of the chamfer than in the case of chamfering in a straight line. As a result, it is necessary to design the width of the core large in advance. On the other hand, by chamfering the end portion in a straight line, it is possible to effectively remove the deformation that has occurred at the end portion without excessively increasing the width of the core.

The edge of the end portion on the outer peripheral surface of the outer cylindrical member may be C-chamfered. According to the above configuration, it is possible to more effectively eliminate the deformation occurring at the end portion without excessively increasing the width of the core.

The dimension of the C chamfer may be 0.3 mm or more. According to the above configuration, it is possible to secure a chamfered portion enough to sufficiently remove the resin having deformation.

The dimension of the C chamfer may be 2.5 mm or less. According to the above structure, it is possible to effectively prevent the separator from being wound around the point where the chamfer is performed.

The dimension of the C chamfer may be one third or less of the thickness of the outer cylindrical member. According to the above configuration, it is possible to sufficiently reduce the possibility of breakage or defects.

Further, the edge of the end portion on the inner circumferential surface of the inner cylindrical member may be chamfered in a straight line. According to the above arrangement, it is easy to insert the shaft for rotating the separator winding core into the inner cylindrical member.

The separator winding spindle related to the present invention may be any of ABS resin, polyethylene resin, polypropylene resin, polystyrene resin, polyester resin, and vinyl chloride resin. According to the above configuration, the core can be manufactured by resin molding using a metal mold.

The separator winding related to the present invention is characterized by being a separator winding in which a separator is wound on the outer peripheral surface of the outer cylindrical member of the separator winding cage. According to the above configuration, it is possible to provide a separator winding that supplies a high-quality separator with little deformation of the separator.

The present invention can provide a separator winding having a strong strength and little deformation of the separator and a separator winding for supplying a separator for a nonaqueous electrolyte secondary battery wound around the separator winding because the deformation of the resin at the end portion is small, .

1 is a schematic view showing a sectional configuration of a lithium ion secondary battery.
Fig. 2 is a schematic diagram showing the state of the lithium ion secondary battery shown in Fig. 1 in each state. Fig.
Fig. 3 is a schematic diagram showing a state of the lithium ion secondary battery in another configuration. Fig.
4 is a schematic view showing a configuration of a slit apparatus for slitting a separator.
5 is a front view of a separator winding core and a separator winding body in which a separator is wound around a separator winding core according to an embodiment of the present invention.
6 is a sectional view of a separator winding core according to an embodiment of the present invention.
7 is an enlarged view of the outer circumferential surface of the outer cylindrical member in the separator core of the separator winding according to the embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to Figs. 1 to 7. Fig. Hereinafter, a heat-resistant separator for a battery such as a lithium ion secondary battery will be described as an example of a separator for a nonaqueous electrolyte secondary battery wound around a separator core (core) related to the present invention.

≪ Configuration of Lithium Ion Secondary Battery >

First, a lithium ion secondary battery will be described with reference to Figs. 1 to 3. Fig.

BACKGROUND ART A non-aqueous electrolyte secondary battery represented by a lithium ion secondary battery has a high energy density and is currently used as a battery for use in mobile devices such as personal computers, mobile phones, portable information terminals, And is widely used as a stationary battery for contributing to the stable supply of electricity.

1 is a schematic diagram showing a sectional configuration of a lithium ion secondary battery 1.

1, the lithium ion secondary battery 1 includes a cathode 11, a separator 12, and an anode 13. As shown in Fig. The external device 2 is connected between the cathode 11 and the anode 13 on the outside of the lithium ion secondary battery 1. [ Then, when the lithium ion secondary battery 1 is charged, electrons move in the direction A, and in the discharge, electrons move in the direction B.

<Separator>

The separator 12 is disposed between the cathode 11, which is the positive electrode of the lithium ion secondary cell 1, and the anode 13, which is the negative electrode, so as to be sandwiched therebetween. The separator 12 separates the cathode 11 and the anode 13, and enables the movement of lithium ions therebetween. As the material of the separator 12, for example, a polyolefin such as polyethylene, polypropylene or the like is used.

Fig. 2 is a schematic view showing the state of the lithium ion secondary cell 1 shown in Fig. 1 in each state. 2 (a) shows a typical state, (b) shows a state when the temperature of the lithium ion secondary battery 1 is raised, (c) shows a state when the lithium ion secondary battery 1 is rapidly heated .

As shown in Fig. 2 (a), the separator 12 has a plurality of holes P formed therein. Normally, the lithium ions 3 of the lithium ion secondary battery 1 can pass through the hole P.

Here, for example, the lithium ion secondary battery 1 may be heated up due to overcharge of the lithium ion secondary battery 1 or a large current caused by a short circuit of external equipment. In this case, as shown in FIG. 2 (b), the separator 12 is melted or softened, and the hole P is closed. Then, the separator 12 is contracted. As a result, the traveling of the lithium ions 3 is stopped, so that the above-described temperature rise is also stopped.

However, when the lithium ion secondary battery 1 is rapidly heated, the separator 12 shrinks abruptly. In this case, as shown in Fig. 2 (c), the separator 12 may be broken. Since the lithium ions 3 leak from the broken separator 12, the passage of the lithium ions 3 does not stop. Therefore, the temperature rise continues.

<Heat-resistant separator>

Fig. 3 is a schematic diagram showing a state of the lithium ion secondary battery 1 of another structure in each state. Fig. 3 (a) shows a typical state, and Fig. 3 (b) shows a state in which the lithium ion secondary battery 1 is rapidly heated.

As shown in FIG. 3A, the lithium ion secondary battery 1 may further include the heat resistant layer 4. The heat resistant layer 4 can be formed on the separator 12. [ 3 (a) shows a structure in which a heat-resistant layer 4 as a functional layer is formed on the separator 12. As shown in Fig. Hereinafter, a film in which the heat resistant layer 4 is formed on the separator 12 is referred to as a heat resistant separator 12a as an example of the separator in which the functional layer is formed. The separator 12 in the separator in which the functional layer is formed is used as the base material for the functional layer.

3 (a), the heat resistant layer 4 is laminated on one surface of the separator 12 on the cathode 11 side. The heat resistant layer 4 may be laminated on one side of the separator 12 on the anode 13 side or may be laminated on both sides of the separator 12. In the heat-resistant layer 4, the same hole as the hole P is formed. Normally, the lithium ions 3 pass through the hole P and the hole of the heat resistant layer 4. The heat-resistant layer 4 contains, for example, a wholly aromatic polyamide (aramid resin) as its material.

Since the heat resistant layer 4 assists the separator 12 even if the lithium ion secondary battery 1 is rapidly heated up and the separator 12 is melted or softened as shown in FIG. 3 (b) The shape of the separator 12 is maintained. Therefore, the separator 12 is melted or softened so that the hole P is blocked. As a result, the traveling of the lithium ions 3 is stopped, so that the overdischarge or overcharge described above is also stopped. Thus, breakage of the separator 12 is suppressed.

&Lt; Manufacturing process of separator / heat-resistant separator &gt;

The production of the separator and the heat-resistant separator of the lithium ion secondary battery 1 is not particularly limited, and can be carried out by a known method. Hereinafter, it is assumed that a porous film as a raw material of a separator (heat-resistant separator) mainly contains polyethylene as its material. However, even when the porous film contains other materials, a separator (heat-resistant separator) can be produced by the same manufacturing process.

For example, a method of adding an inorganic filler or a plasticizer to a thermoplastic resin, forming the film, and then washing and removing the inorganic filler and the plasticizer with an appropriate solvent. For example, in the case of a polyolefin separator in which the porous film is formed of a polyethylene resin containing ultrahigh molecular weight polyethylene, it can be produced by the following method.

The method includes (1) a kneading step of kneading ultrahigh molecular weight polyethylene, an inorganic filler (e.g., calcium carbonate, silica) or a plasticizer (e.g., low molecular weight polyolefin, liquid paraffin) to obtain a polyethylene resin composition, (3) a step of removing the inorganic filler or plasticizer from the film obtained in the step (2); and (4) a step of stretching the film obtained in the step (3) Thereby obtaining a porous film. The step (4) may be carried out between the steps (2) and (3).

By the removal process, a plurality of micropores are formed in the film. The micropores of the film stretched by the stretching process become the aforementioned hole (P). Thereby, a porous film (separator 12) which is a polyethylene microporous membrane having a predetermined thickness and permeability can be obtained.

In the kneading step, 100 parts by weight of ultrahigh molecular weight polyethylene, 5 to 200 parts by weight of a low molecular weight polyolefin having a weight average molecular weight of 10,000 or less, and 100 to 400 parts by weight of an inorganic filler may be kneaded.

Thereafter, in the coating step, the heat resistant layer 4 is formed on the surface of the porous film. For example, an aramid / NMP (N-methyl-pyrrolidone) solution (coating solution) is applied to a porous film to form a heat resistant layer 4 which is an aramid heat resistant layer. The heat-resistant layer 4 may be formed on only one side of the porous film, or on both sides of the porous film. As the heat resistant layer 4, a mixed solution containing a filler such as alumina / carboxymethyl cellulose may be coated.

In the coating process, a polyvinylidene fluoride / dimethylacetamide solution (coating liquid) is applied (coating step) to the surface of the porous film, and an adhesive layer is formed on the surface of the porous film by precipitation It is possible. The adhesive layer may be formed on only one side of the porous film or on both sides of the porous film.

The method of coating the coating solution on the porous film is not particularly limited as long as it can uniformly wet-coat it, and conventionally known methods can be employed. Examples of the coating method include a capillary coating method, a spin coating method, a slit die coating method, a spray coating method, a dip coating method, a roll coating method, a screen printing method, a flexo printing method, a bar coater method, And the like. The thickness of the heat resistant layer 4 can be controlled by the thickness of the coating wet film and the solid content concentration in the coating liquid.

A resin film, a metal belt, a drum, or the like can be used as a support for fixing or transporting the polyolefin-based porous film when coating.

As described above, the separator 12 (heat-resistant separator) in which the heat resistant layer 4 is laminated on the porous film can be produced. The fabricated separator is wound around a cylindrical core. In addition, the object to be produced by the above production method is not limited to the heat resistant separator. This manufacturing method does not need to include a coating process. In this case, the object to be produced is a separator having no heat resistant layer.

<Slit device>

(Hereinafter referred to as &quot; separator &quot;) having no heat resistant separator or heat resistant layer is preferably a width (hereinafter, referred to as &quot; product width &quot;) suitable for applications such as the lithium ion secondary battery 1 and the like. However, in order to increase the productivity, the separator is manufactured such that its width is equal to or greater than the product width. And, once manufactured, the separator is cut (slit) into a product width.

The &quot; width of the separator &quot; means the length of the separator in parallel with the plane in which the separator extends and also in the direction perpendicular to the longitudinal direction of the separator. Hereinafter, a separator having a wide width before slitting will be referred to as a &quot; fabric &quot;, and a slit separator will be specifically referred to as a &quot; slit separator &quot;. The slit means that the separator is cut along the longitudinal direction (the direction of flow of the separator in the production process, MD: Machine direction), and the cut means that the separator is cut along the transverse direction it means. The transverse direction (TD) means a direction which is parallel to the plane in which the separator extends and is also substantially perpendicular to the longitudinal direction (MD) of the separator.

Fig. 4 is a schematic view showing a constitution of a slit apparatus 6 for slitting a separator. Fig. 4 (a) shows the overall configuration, and Fig. 4 (b) shows the configuration before and after slitting the fabric.

4A, the slit apparatus 6 includes a cylindrical roller 61, rollers 62 to 69, and a plurality of take-up rollers 62, (70U, 70L).

<Slit Before>

In the slit apparatus 6, a cylindrical core (c) having a rounded end is sandwiched between the unwinding rollers (61). As shown in Fig. 4 (b), the farthest end is wound on the path (U or L) from the core (c). The unwound fabric is conveyed to the roller 68 via the rollers 63 to 67. [ In the process of being transported, the fabric is slit into a plurality of separators. Further, in order to transport the fabric in a desired trajectory, the number and arrangement of the rollers 62 to 69 may be changed.

<After the slit>

 As shown in Fig. 4 (b), a part of the plurality of slit separators is wound on each of the cylindrical cores u (separator winding core) sandwiched by the winding roller 70U. Another part of the plurality of slit separators is wound around each of the cylindrical cores 1 (separator winding core) sandwiched between the winding rollers 70L. Further, the integral body of the slit separator and the core (u 占) rolled up in a roll is referred to as &quot; winding body (separator winding body) &quot;.

The present invention relates to a core (separator winding core) in which a separator for a nonaqueous electrolyte secondary battery such as the slit separator is wound, and a separator winding in which a separator for a nonaqueous electrolyte secondary battery is wound around the core.

&Lt; Separator winding core and separator winding body &

Hereinafter, the separator core of the present invention will be described with reference to Figs. 5 to 7. Fig.

5 is a front view of a core and a separator winding in which a separator is wound around the core.

The separator 12 is fixed to the outer cylindrical member 101 with a constant tension while rotating the core 100 while sandwiching a shaft such as a winding roller on the inner cylindrical member 102 of the core 100 shown in Fig. The separator winding body 110 shown in Fig. 5 (b) can be manufactured.

The core 100 described above can be adapted to the core (u, l) of the slit device 4 shown in Fig. 4, for example. That is, the winding of the separator 12 using the core 100 can be performed in the same manner as described above.

 <Core Structure>

The core 100 shown in Fig. 5 (a) includes an outer cylindrical member 101, an inner cylindrical member 102, and a plurality of ribs 103. The outer cylindrical member 101 defines the outer peripheral surface of the core 100 on which the separator is wound. The inner cylindrical member 102 is formed on the inner side of the outer cylindrical member 101 and functions as a bearing in which a shaft such as a winding roller for rotating the core is fitted. The rib 103 is a support member extending in the radial direction between the outer cylindrical member 101 and the inner cylindrical member 102 and connected to both.

In this embodiment, the ribs 103 are arranged so as to be perpendicular to the outer cylindrical member 101 and the inner cylindrical member 102 at positions spaced equally from each other and divided into eight equal parts. However, the number of ribs and the spacing of the ribs are not limited to this.

It is preferable that the centers of the circumferences of the outer cylindrical member 101 and the inner cylindrical member 102 are substantially aligned, but the present invention is not limited thereto. The thickness of the outer cylindrical member 101 and the inner cylindrical member 102, the width of the outer peripheral surface, and the dimensions such as the radius can be appropriately designed according to the type of the separator for the non-aqueous electrolyte secondary battery to be manufactured.

As the material of the core 100, a resin containing any of ABS resin, polyethylene resin, polypropylene resin, polystyrene resin, polyester resin, and vinyl chloride resin can be preferably employed. As a result, the core 100 can be manufactured by resin molding using a metal mold.

<45 ° chamfering>

6 is a cross-sectional view taken along line A-A 'of the core 100 shown in Fig. 5 (a).

As shown in Fig. 6, the edges 101A and 101B on the outer peripheral surface of the outer cylindrical member 101 are chamfered by 45 degrees at their edges. Similarly to the end portions 101A and 101B on the outer circumferential surface of the outer cylindrical member 101, the end portions 102A and 102B on the inner circumferential surface of the inner cylindrical member 102 are also chamfered at an angle of 45 ° have.

In the present specification, a 45 ° ± 5 ° chamfer is called a C chamfer. In short, the 45 ° chamfer is a form of C chamfer. From the viewpoint of more effectively removing the deformations at the ends, it is preferable that the C chamfer is 45 DEG +/- 2 DEG, more preferably 45 DEG +/- 1 DEG.

The C chamfer refers to a chamfer obtained by removing a member having a predetermined dimension from the tip end of the edge of the member at an angle of 45 占 占 at the oblique surface of the member. When the edges of the end portions 101A and 101B are substantially perpendicular to each other as exemplified by the outer cylindrical member 101 and the like, the dimension from one edge to the predetermined position on one surface and from the edge to the predetermined position on the other surface is By the same token, when the member is removed from the plane connecting the predetermined positions of the two points, the C chamfer can be realized.

As described above, by chamfering the end portions 101A, 101B, 102A, and 102B of the core 100, it is possible to eliminate the residual deformations caused by the injection molding.

Further, by chamfering the end portions 102A and 102B of the inner cylindrical member 102, it becomes easy to insert the shaft of the take-up roller or the like into the inner cylindrical member 102. [

Examples of the method for forming the chamfer include a method of forming a member having an edge (injection molding) and then cutting the edge, and a method of forming (injection molding) a member by using a die provided with a chamfer shape in advance have. In the case of the former, when the resin inlet (gate) for injection molding is formed in the portion to be chamfered, the gate mark can be removed at the same time as the chamfering. In the latter case, since the resin flows in the mold without being accumulated, the molded body (member) is not easily deformed.

&Lt; C chamfering of outer cylindrical member &gt;

7 is an enlarged cross-sectional view of the outer cylindrical member in the separator core of the separator winding. For the sake of convenience, other members of the separator winding body 110 are not shown.

7 is an enlarged cross-sectional view of the outer cylindrical member 101 of the separator winding 110. Fig.

The separator 12 is wound around the outer circumferential surface of the outer cylindrical member 101 of the core 100. At this time, the separator 12 is not wound at the point where the C chamfer is performed on the outer peripheral surface of the outer cylindrical member 101. As described above, it is possible to prevent breakage or deformation of the separator 12 by winding the separator 12 so as not to catch the chamfering point.

The width of the surface on which the C chamfer is not performed needs to be larger than the width of the separator 12 on the outer peripheral surface of the outer cylindrical member 101 around which the separator 12 is wound. The separator 12 is wound such that the center of the width of the outer circumferential surface of the outer cylindrical member 101 is substantially coincident with the width of the outer circumferential surface of the outer cylindrical member 101 so that the separator 12 is not caught by the C chamfering point on the outer circumferential surface of the outer cylindrical member 101 It is possible to conduct a round.

In order to manufacture such a core 100, the width dimension of the outer cylindrical member 101 is designed in consideration of the width of the separator 12 and the dimension of the C chamfer when the core 100 is injection molded.

In the case of removing the resin with deformation remaining by the C chamfer described above, the dimension of the C chamfer is preferably at least 0.3 mm. If the resin is removed to a size larger than this dimension, the resin in which deformation remains can be sufficiently removed.

The dimension of the C chamfer indicating the distance from the assumed corner position to the position where the chamfer is started in the absence of the chamfer is preferably 2.5 mm or less and more preferably 1 mm or less. With this dimension, it is possible to secure a sufficient point on the outer peripheral surface of the outer cylindrical member 101, on which the separator 12 is wound, without chamfering. Therefore, it is possible to effectively prevent the separator 12 from being wound on the chamfering point of the outer cylindrical member 101. [

In order to remove the resin having the same volume as the C chamfer when removing the resin at the end by performing R chamfering so as to have rounds at the corners, the dimension of the R chamfer is to be made about 1.5 times the dimension of the C chamfer There is a need.

Therefore, the use of the C chamfer rather than the R chamfer makes it possible to prevent the separator 12 from being caught by the chamfering point on the outer peripheral surface of the outer cylindrical member 101, It is possible to reduce the width of the substrate 101.

The width of the outer cylindrical member 101 can be reduced and the core 100 and the separator winding 110 can be reduced in weight and cost.

It is also preferable that the inner cylindrical member 102 be chamfered by C more than the R chamfered on the inner peripheral surface. This is because a shaft having a slope of 45 DEG +/- 5 DEG is easier to insert than an end having a curved surface.

The inner peripheral surface of the outer cylindrical member 101, the outer peripheral surface of the inner cylindrical member 102, and the rib 103 may be chamfered appropriately. As in the above description, C chamfering may be performed, but various chamfering processes such as R chamfering and slit chamfering may be performed.

 When the C chamfer is applied to the outer cylindrical member 101, the inner cylindrical member 102, or the rib 103, it is preferable that the dimensions thereof are one third or less of the thickness of those members. With this dimension, it is possible to sufficiently reduce the possibility of breakage or defects.

In the above description, the cores 100A, 101B, 102A, and 102B are C-chamfered. However, the angle of the chamfer is not limited to 45 DEG, (100) may be subjected to a straight chamfering process on the end portions 101A, 101B, 102A, and 102B.

<Summary>

As described above, the core 100 subjected to the C chamfering has a high strength and is not deformed well because the resin with the deformation remaining is removed. Therefore, the separator winding body 110 in which the separator 12 is wound around the core 100 can provide the separator 12 of high quality with little distortion.

The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims.

1: Lithium ion secondary battery
2: External device
3: Lithium ion
4: Heat resistant layer
11: Cathode
12: Separator
12a: Heat-resistant separator
13: anode
100: Core
101: outer cylindrical member
101A: end
101B: end
102: inner cylindrical member
102A: end
102B: end
103: rib
110: separator winding

Claims (8)

A separator winding in which a separator for a nonaqueous electrolyte secondary battery is wound,
An inner cylindrical member formed on the inner side of the outer cylindrical member; and a plurality of support members extending in a radial direction between the outer cylindrical member and the inner cylindrical member and connected to the inner cylindrical member,
And the edge of the end portion on the outer peripheral surface of the outer cylindrical member is chamfered in a straight line. The method according to claim 1,
And the edge of the end portion on the outer peripheral surface of the outer cylindrical member is C-chamfered. 3. The method of claim 2,
And the dimension of the C chamfer is 0.3 mm or more. The method of claim 3,
Wherein the dimension of the C chamfer is 2.5 mm or less. The method of claim 3,
Wherein the dimension of the C chamfer is equal to or smaller than 1/3 of the thickness of the outer cylindrical member. 6. The method according to any one of claims 1 to 5,
Wherein an edge of an end portion of the inner circumferential surface of the inner cylindrical member is chamfered in a straight line. 7. The method according to any one of claims 1 to 6,
A separator core comprising a material selected from the group consisting of an ABS resin, a polyethylene resin, a polypropylene resin, a polystyrene resin, a polyester resin, and a vinyl chloride resin. A separator winding wherein a separator for a nonaqueous electrolyte secondary battery is wound on an outer peripheral surface of an outer cylindrical member of the separator winding cage according to any one of claims 1 to 7.

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